00365nam a22001337a 4500020001800000082001700018100001700035245007100052250001200123260003300135300002000168650002600188700001700214  a9788120338531  a515.3bAHS/T  aAhsan Akhtar  aTextbook of differential calculus/ cAhsan Akhtar and Sabiha Ahsan  a2nd ed.  aDelhi:bPHI learning,c2015.  a451p. ; b25cm.  aDifferential Calculus  aSabiha Ahsan